Conventionally, a connector body for this kind of noinsertion force connector assembly generally has a thin and elongated slit on the front surface of a housing which extends in its longitudinal direction so that the connector portion of the print circuit board may be inserted within this slit. Arrayed along at least One Of surfaces Of the slit is a plurality of contact members each corresponding to a plurality of contact terminals provided at the connector portion of the print circuit board. Each contact member is comprised of a connecting terminal at its one end for being connected to the external circuit and a resilient member having a contact at its other end. It is retained at a retracted position where its contact is not in contact with the contact terminal of the print circuit board until the connector body and the connector portion of the print circuit board are placed in a predetermined coupling position. Therefore, the insertion force is not practically necessary or is not necessary at all when the print circuit board is inserted. After the connector body and the print circuit board connector portion are placed at the predetermined coupling position, each contact member is resiliently deformed so that its contact advances up to a position where it comes in contact with its corresponding contact terminal, and is retained at this position to thereby achieve a desired electrical connection.
A means for resiliently deforming each contact member so that its contact advances up to the position where it comes in contact with the corresponding contact terminal comprises a float member slidably provided on the housing of the connector body and a bar member for resiliently deforming each contact member by shifting the float member toward a front aperture portion of the slit so that its contact comes in contact with the contact terminal of the print circuit board.
In the conventional no-insertion force connector assembly, after the connector portion is inserted into the slit of the connector body, a bar is inserted from a bar insertion hole of the connector body to force the float up to resiliently deform the contact member so that a desired electrical contact may be achieved. In that process, each contact member, which has the same total length, simultaneously comes in contact with the contact terminal of the connector portion of the print circuit board when the contact members are resiliently deformed by the same amount. That is, since all the contact members are necessary to be simultaneously deformed, a high insertion force is needed when the bar is inserted.
In addition, in the conventional no-insertion force connector assembly, the total lengths and the electrical contact positions of all the contact members are equal as measured in their longitudinal direction, and the positions of the contact terminals of the print circuit board connector portion are the same over the entire array. In consequence, the contact terminal at the connector portion of the print circuit board cannot be set in its width to below a certain limit in view of the reliability of the electrical connection between it and the contact member. This poses a certain constraint in reducing the distance between the adjacent contacts, that is, the pitch.
Accordingly, an object of the present invention is to provide a no-insertion force connector assembly which allows the insertion force to be reduced as the bar is inserted.
Another object of the present invention is to provide a no-insertion force connector assembly which allows the distance between the adjacent contacts, that is, the pitch to be made small as compared with the conventional one.